Sand particles sampling efficiency

Figure 13 illustrates that the sampling efficiency appears to be independent of the probe relative wall thickness at sampling velocities equal to and higher than the upstream local velocity. This observation contrasts with the results obtained with the sand particles shown in Figure 11. This difference can be explained as follows In the presence of a blunt probe, the fluid streamlines deflect ahead of the probe nozzle even at a velocity ratio U/Uq =...

Figure 4. Predicted and observed sampling efficiencies for the 0.45-mm sand particles. (Reproduced with permission from reference 34. Copyright 1984.)...

The high combustion efficiency of a fluid bed results in a reduced amount of inorganic material as fine ash. The remaining larger material consists mainly of noncombustibles, such as rocks, and wire brought in with the fuel, and coarse sand-Uke neutral particles. Low combustion temperatures in the fluidized bed minimize the formation of toxic materials that might go into the ash. Ash samples from FBC systems have consistently tested nontoxic, and in many instances the ash is being sold as input for other products such as cement. 

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